wiring AUDI A6 1995 C5 / 2.G AHA Engine Multiport Fuel Injection And Ignition System User Guide

24-39
If there is no voltage:

If there is still no voltage: - Connect multimeter between harness connector terminal 1 (to ECM)
and vehicle Ground, using VW1594 connector test kit.
Specified value: 11.0-14.5 volts
- Check wiring between terminal 1 and relay panel using appropriate
wiring diagram.
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24-41
If there is no voltage:

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

If wiring is OK: - Check wiring for open circuit between ECM/test box and 4-pin HO2S
harness connector (to ECM).

Connector terminal 2 to ECM/test box socket 27
Specified value: max. 1.5
- Replace Motronic ECM -J220- page 01
-68
- Initiate adaptation of throttle valve control module to ECM page 24
-
150
.
- Check readiness code page 01
-70
. If Diagnostic Trouble Code
(DTC) memory has been erased, or ECM was disconnected, generate
new readiness code page 01
-73
.
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Wiring diagram

Test requirements
Engine Coolant Temperature (ECT) at least
80 C (176 F)
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24-46
Evaluation of display group 36 Display group:
36


Display fields:
1, 3
Possible malfunction cause
Corrective action
approx. 0.435 V

Open circuit in wire -4- between oxygen sensor and
ECM - Check reference voltage page 24
-47
approx. 0.440 V

Open circuit in wire -3- between oxygen sensor and
ECM
approx. 1.085 V
Short circuit to B+ in wire -4- between oxygen sensor
and ECM - Check O2S wiring, bank 1, sensor 2
page 24
-48

- Check O2S wiring, bank 2, sensor 2
page 24
-50

approx. 0.000 V

Short circuit to Ground in wire -4- between oxygen
sensor and ECM
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24-47

Checking O2S reference voltage

- Disconnect 4-pin connector for respective
Oxygen Sensor (O2S) behind Three Way
Catalytic Converter (TWC).

If voltage is NOT OK:
If voltage is OK: - Connect multimeter US1119 (Fluke 83 or equivalent) between harness
connector terminals 3 and 4 (to ECM), using adapter cables from
VW1594 connector test kit.
- Start engine and measure voltage.
Specified value: 0.40 to 0.50 volts
- Switch ignition off.
- Check O2S wiring.

Bank 1, sensor 2 page 24
-48
.

Bank 2, sensor 2 page 24
-50
.
- Replace respective O2S behind TWC.
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11/23/2002 htt
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play?action=Goto&t
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pair&id=AUDI.B5.FU03.24.1

24-48

Checking O2S wiring, bank 1, sensor 2

- Disconnect 4-pin connector (green) for Oxygen
Sensor (O2S) behind Three Way Catalytic
Converter (TWC) -G130-.

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

- Check wiring for open circuit between ECM/test box and 4-pin O2S
harness connector (to ECM).

Connector terminal 3 to ECM/test box socket 51
Connector terminal 4 to ECM/test box socket 52
Specified value: max. 1.5
- Check wiring for short circuits between terminals of 4-pin connector.

Connector terminal 4 to ECM/test box socket 51
Specified value:
- Check shielding wire for short circuit to sensor wires.

Connector terminal 4 to ECM/test box socket 14
Connector terminal 3 to ECM/test box socket 14
Specified value:
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11/23/2002 htt
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play?action=Goto&t
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pair&id=AUDI.B5.FU03.24.1

24-49
If wiring is OK:

- Replace Motronic ECM -J220- page 01
-68
.

- Carry out adaptation of throttle valve control
module to ECM page 24
-150
.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
Pa
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port Fuel In
jection
(MFI
) and i
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU03.24.1

24-50

Checking O2S wiring, bank 2, sensor 2

- Disconnect 4-pin connector (brown) for Oxygen
Sensor (O2S) 2 behind Three Way Catalytic
Converter (TWC) -G131-.

- Connect VAG1598/22 test box to ECM harness
connector page 01
-67
.

- Check wiring for open circuit between ECM/test box and 4-pin O2S
harness connector (to ECM).

Connector terminal 3 to ECM/test box socket 38
Connector terminal 4 to ECM/test box socket 50
Specified value: max. 1.5
- Check wiring for short circuits between terminals of 4-pin connector.

Connector terminal 4 to ECM/test box socket 38
Specified value:
- Check shielding wire for short circuit to sensor wires.

Connector terminal 4 to ECM/test box socket 14
Connector terminal 3 to ECM/test box socket 14
Specified value:
Pa
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) and i
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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pair&id=AUDI.B5.FU03.24.1

24-51
If wiring is OK:

- Replace Motronic ECM -J220- page 01
-68
.

- Carry out adaptation of throttle valve control
module to ECM page 24
-150
.

- Check readiness code page 01
-70
. If
Diagnostic Trouble Code (DTC) memory has
been erased, or ECM was disconnected,
generate new readiness code page 01
-73
.
Pa
ge 64 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU03.24.1

24-52

Oxygen Sensor (O2S) heater behind
TWC, checking


Notes:

Connector for Oxygen Sensor (O2S) heater
(behind TWC) -Z29- (bank 1, sensor 2): 4-pin,
green
Connector for Oxygen Sensor (O2S) 2 (behind
TWC) -Z30- (bank 2, sensor 2): 4-pin, brown
Component locations page 24
-1

Required special tools and test equipment

VAG1551 or VAG1552 Scan Tool (ST) with
VAG1551/3 adapter cable
VAG1598/22 test box
Multimeter US1119 (Fluke 83 or equivalent)
VW1594 connector test kit
Wiring diagram
Pa
ge 65 of 166 Motronic Multi
port Fuel In
jection
(MFI
) and i
gnition s
ystem
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.1